RSpec On Rails

In the previous post Do it RSpec the usage of RSpec in a Ruby project was described generally. This post explains how to code a simple RSpec test in a Ruby on Rails project.
The installation of RSpec itself is alike:

user$ gem install rspec

In a Rails project the rspec-rails gem has to be added to the Gemfile:

gem "rspec-rails", :group => [:test, :development]

Runing the Bundler:

user$ bundle

and preparing the Rails project for RSpec tests:

user$ rails g rspec:install

It generates the subfolder spec and a spec helper within. The spec helper file contains logic considering all tests. At this point only testing models is covered. That's why creating the folder:

user$ mkdir spec/models

Generating the model:

user$ rails g model Person name:string surname:string birthday:date active:boolean

The generated models/person.rb looks blank like:

class Person < ActiveRecord::Base
  attr_accessible :birthday, :name, :surname, :active
end

Some tests require test objects, called fixtures. Creating the folder for them:

user$ mkdir spec/fixtures

Fixtures are defined in a YAML notation, e.g.:

david:
id: 1 
name: David
surname: Heinemeier Hansson 
birthday: 1979-10-15

Saving this single fixture in the file spec/fixtures/people.yml. Please keep in mind, the more fixtures you create for several tests the harder to maintain changes of fixtures.
Creating the spec/models/person_spec.rb:

require 'spec_helper'

describe Person do
  fixtures :people
    
  before(:each) do
    @person = people(:david)
  end

  it "should not be valid without a name" do
    @person.name = ''
    @person.should_not be_valid
  end

  it "should be activated before validation" do
    @person.create.should be_active
  end
end

That are pretty little specifications. Before fullfilling them, the test was run:

user$ rspec spec/models/person_spec.rb

it returns:

Failures:

  1) Person should not be valid without a name
     Failure/Error: @person.should_not be_valid
       expected valid? to return false, got true
     # ./spec/models/person_spec.rb:12:in `block (2 levels) in '

  2) Person should be activated before validation
     Failure/Error: @person.should be_active
       expected active? to return true, got false
     # ./spec/models/person_spec.rb:17:in `block (2 levels) in '

Finished in 0.09145 seconds
2 examples, 2 failures

Implementing the logic to achieve the goals by enhancing the models/person.rb:

class Person < ActiveRecord::Base
  attr_accessible :birthday, :name, :surname, :active
  validates_presence_of :name
end

Again the test:

Failures:

  1) Person should be activated before validation
     Failure/Error: @person.should be_active
       expected active? to return true, got false
     # ./spec/models/person_spec.rb:17:in `block (2 levels) in '

Finished in 0.17313 seconds
2 examples, 1 failure

First requirement is satisfied. Enhancing the same model to strike the second:

class Person < ActiveRecord::Base
  attr_accessible :birthday, :name, :surname
  validates_presence_of :name
  before_validation :activate

private
  def activate
    self.active = true
  end
end

Running the tests again:

Finished in 0.11393 seconds
2 examples, 0 failures

signals: mission accomplished!

Supported by Ruby 2.1, RubyOnRails 3.2.17 and RSpec 2.12.0